Fruit harvesting machines such as grape harvesters commonly are equipped with a shaker assembly which straddles a row of shrubs or vines. The shaker assembly comprises sets of shaker rods which are oscillated to beat or shake the vines vigorously to detach the grapes or bunches of grapes from the vine shrubs. The detached fruit is guided into conveyors on both sides of the vines and transported by these conveyors to bins or containers on top of the grape harvester. When the machines reach the end of a vine row, the bins may be unloaded into a towed cart for further transport to the winery.
The action of the shaker rods on the vines also detaches some foliage therefrom. The loose leaves and leaf portions are equally received in the conveyors and are conveyed along with the grapes towards the bins. Conventionally the harvesting machine is equipped with cleaning mechanism for separating the leaves and other foreign material such as detached wood from the fruit. For example the New Holland Braud grape harvester model SB64 has below the upper run of each conveyor an transverse apron conveyor for receiving the detached crop material and tipping the same into a bin on each side of the harvester. Over the discharge end of the apron a fan has been installed for extraction of the leaves from the crop material on the apron. The cleaning action is enhanced by the air stream acting on the crop during its fall into the bins.
It has been observed that the fan not only sucks away the foliage, but also drops of valuable fruit juice. The fruit juice is produced by grape berries which are burst under the impact of the shaker rods. At the discharge end of the apron conveyor, the air flow sucks away the juice drops and ejects them together with the leaves through a duct aside the machine. These losses can be reduced by decreasing the fan speed in order to diminish air speeds, but such action inevitably also reduces the proportion of foreign material which is removed from the crop.
FR-A-2.686.530 proposes to provide the fruit harvester with a cleaning system comprising inwardly extending rods retaining the leaves, a mesh funnel installed beneath the rods retaining the grape bunches and the berries, and a full plate funnel receiving the fruit juice which migrated between the rods and through the mesh funnel. Such system is voluminous in size and prone to pollution by crop material sticking to the inner or outer funnels. Furthermore there is no easy access for cleaning the polluted components.
FR-A-2.298.266 discloses a conveyor and cleaning system including conveyor cups or buckets which are provided with transverse ribs for retaining thereon the leaves. Loose grapes and juice are received in tub sections below or between the ribs. The buckets are provided with air inlets on their sides for allowing an effective upward air stream removing the leaves from the ribs. Such arrangement drastically reduces the conveying capacity of the buckets. Furthermore the lower section of the buckets is partially closed such that crop and other material can easily accumulate therein, while access for cleaning is seriously hindered.
FR-A-2.795.599 shows a mesh conveyor installed above a container, the conveyor allowing the passage therethrough of loose berries and juice and conveying grapes and leaves towards an extraction fan. In order to prevent accumulation of crop material between the upper and lower runs of the conveyor, the latter comprises movable louvers which present smaller meshes in their upper run and larger meshes in their lower run. Such apparatus requires frequent cleaning of the conveyor to ensure that the louvers remain movable and do not get stuck in the one or other position by the drying juice.